1. Field of the Invention
The instant invention is one such as would be noted to be within that particular field of devices consisting of screws, bolts and the like.
2. Related Art
Your inventor is unaware of any art such as would serve to anticipate the instant invention.
The instant invention is a screw. The head of the screw is cylindrically shaped with a pair of equivalent and opposing curved grooves cut therein. It is the presence of these grooves that operates to transform the head into a novel and unique cutting head. The angular pitch with reference to the horizontal is the same for both grooves and equals as well the pitch of the threading found on the shank portion of the screw. Within the top side of the cutting head of the invention there is to be found a closed hole for receipt of the tip of a screwdriver or alternatively, drill bit. Typically though not necessarily, the closed hole is triangular in shape for receipt of a similarly shaped screwdriver or alternatively, drill bit. Moreover, serrated edging circumscribes a portion of the perimeter of the bottom side of the cutting head of the preferred embodiment of the instant invention. The lower portion of the shank of the screw is characterized by the presence of an elongated concave shaped self-tapping cutter that conjoins with the shank of the screw in respect of terminating in a sharp point.
Finished carpenters virtually always find it desirable to be able to insert a screw clearly into wood and, in particular, hardwood, in such a manner that once in it will remain in place tightly positioned and not likely to loosen over time.
The instant invention serves to maximize the probability that such will indeed prove to be the case. The self-tapping cutter of the instant invention coupled with the curved grooves within the head of the screw allow for expulsion of wood debris from a hole therein being created simultaneously with the screwing therein of the instant invention. This phenomenon intrinsically characteristic of the process of so utilizing the instant invention results in the formation of a tight, clean screw hole free of wood debris within which the instant invention fits very tightly, neatly and with virtually no propensity for eventual loosening. An especially unique feature of the invention such as serves to greatly facilitate such an outcome is one wherein the angularity of each of the curved grooves and that of the pitch of all of the threading on the shank portion of the screw is one and the same. Moreover, given the unique characteristics of the instant invention, it can be placed on a drilling chuck and drilled directly into a wood surface without any need whatsoever to initially drill a hole for it to be inserted into. Thus, an object of saving work time while likewise maximizing screw hole tightness is uniquely addressed. Also, the instant invention is readily amenable to being countersunk into wood and then filled over so as to completely obscure its presence at all within the wood into which it would have been applied. This feature addresses the object of enhancing aesthetics as respects finish carpentry work. Finally, the triangularly shaped closed hole within the top of the cutting head portion of the instant invention serves to facilitate minimization of any propensity for slippage or so-called stripping of a screw like device while at the same time providing a means for applying maximum torque in respect of turning the instant invention into wood, for example, on the end of a rapidly turning drill. The instant invention is moreover where desired also amenable to being inserted and countersunk into metal as well.
In view of the foregoing, it is respectfully submitted that the instant invention is indeed not only new and unique but unquestionably useful.